Fix test_run_gxtool_randomlines test on Galaxy dev branch

which was failing with:

```
E           galaxy.tool_util.provided_metadata INFO 2023-06-19 12:49:16,823 [pN:main.1,p:15735,tN:LocalRunner.work_thread-0] One or more tool outputs is marked as failed ({'type': 'dataset', 'ext': 'data', 'dataset_id': 1, 'stderr': 'Unable to fetch file:///home/runner/work/planemo/planemo/tests/data/hello.txt\nCould not find handler for URI [file:///home/runner/work/planemo/planemo/tests/data/hello.txt]', 'failed': True}).
```

After galaxyproject/galaxy#15497 and
follow-up galaxyproject/galaxy#15794 ,
data upload using "file://" URLs is allowed only for Galaxy admins.
This adds a basic ``file_sources_conf.yml`` configuration file that
allows planemo to upload from the test data directory.

planemo/galaxy/config.py

@@ -103,6 +103,14 @@
 </job_metrics>
 """
 
+FILE_SOURCES_TEMPLATE = """
+- type: posix
+  root: '${test_data_dir}'
+  id: test_data_dir
+  label: Test data directory
+  doc: Test data directory for the runnables being tested
+"""
+
 TOOL_SHEDS_CONF = """<tool_sheds>
   <tool_shed name="Target Shed" url="${shed_target_url}" />
 </tool_sheds>
@@ -362,6 +370,7 @@ def config_join(*args):
         all_tool_paths = _all_tool_paths(runnables, galaxy_root=galaxy_root, extra_tools=kwds.get("extra_tools"))
         _handle_job_config_file(config_directory, server_name, test_data_dir, all_tool_paths, kwds)
         _handle_job_metrics(config_directory, kwds)
+        _handle_file_sources(config_directory, test_data_dir, kwds)
         _handle_refgenie_config(config_directory, galaxy_root, kwds)
         file_path = kwds.get("file_path") or config_join("files")
         _ensure_directory(file_path)
@@ -1384,6 +1393,13 @@ def _handle_job_metrics(config_directory, kwds):
     kwds["job_metrics_config_file"] = metrics_conf
 
 
+def _handle_file_sources(config_directory, test_data_dir, kwds):
+    file_sources_conf = os.path.join(config_directory, "file_sources_conf.yml")
+    file_sources_conf_contents = _sub(FILE_SOURCES_TEMPLATE, {"test_data_dir": test_data_dir})
+    write_file(file_sources_conf, file_sources_conf_contents)
+    kwds["file_sources_config_file"] = file_sources_conf
+
+
 def _handle_refgenie_config(config_directory, galaxy_root, kwds):
     refgenie_dir = os.path.join(config_directory, "refgenie")
     _ensure_directory(refgenie_dir)

tests/test_run.py

@@ -66,6 +66,8 @@ def test_run_gxtool_randomlines(self):
                 "--no_dependency_resolution",
                 "--galaxy_branch",
                 target_galaxy_branch(),
+                "--test_data",
+                TEST_DATA_DIR,
                 tool_path,
                 job_path,
             ]